PV Degradation Factor

Configuration
1

Hello fellow HA enthusiast!
I made an esphome solar immersion device wich calibrated gives me available solar pv power and it’s working fine at the moment. What i’m trying now is create a new template sensor that accounts for usual PV degradation. I need a factor that increases over time so that in 20 years, available solar power is smaller by 20%.
power@install_time*degradation_factor=power_now how?

2

20% in 20 years is 1% per year, which is 1/365.25% per day.

You need a sensor or helper that adds 0.002738% per day.

You could do it with a triggered template sensor.

template:
  - trigger:
      - platform: time
        at: "01:06:00" # or pick another time of day to increase this
    sensor:
      - name: "Cumulative PV Degradation"
        state: "{{ this.state|float(0) + 0.002738 }}"
        unit_of_measurement: "%"
1 Like
3 
- sensor:
      - name: "available_pv_power"
        unit_of_measurement: "W"
        icon: mdi:solar-power
        device_class: power
        state_class: measurement
        state: >
          {% set days_after_install = ( (  as_timestamp(now()) - as_timestamp(strptime("24.09.2022", "%d.%m.%Y")) ) / 86400 ) | float | round(4) %}
          {% set available_solar_initial = states('sensor.available_pv_power_initial') | float %}
          {% if is_number(states('sensor.available_pv_power_initial'))  %}
          {{ (available_solar_initial-(days_after_install*0.2*available_solar_initial/7300))|round(0) }}
          {% else %}
            None
          {% endif %}

I heavily edited the “days after quit smoking” HA template and I thisk this works too.

4

Or if you want to do it using dates (which is probably safer), it’s 31.69x10-9 % per second, so, create an input datetime with your install date in it and…

template:
  sensor:
    - name: "Cumulative PV Degradation"
      state: "{{ (state_attr('input_datetime.install_date', 'timestamp')|int - now().timestamp()) * 31.69e-9 }}"
      unit_of_measurement: "%"

It’s pretty useless storing the install date in a datetime as it will not change, just put the timestamp of the date in the template. You can work out what it is here https://www.epochconverter.com/

template:
  sensor:
    - name: "Cumulative PV Degradation"
      state: "{{ (1664029275 - now().timestamp()) * 31.69e-9 }}"
      unit_of_measurement: "%"
1 Like